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1.
Nature ; 462(7273): 620-3, 2009 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-19935645

RESUMEN

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated gamma-ray emission. Galactic 'microquasars', which are binary systems consisting of a neutron star or stellar-mass black hole accreting gas from a companion star, also produce relativistic jets, generally together with radio flares. Apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar, with the consequence that we are as yet unsure about the mechanism of jet energization. Here we report four gamma-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 (an exceptional X-ray binary that sporadically produces radio jets). There is a clear pattern of temporal correlations between the gamma-ray flares and transitional spectral states of the radio-frequency and X-ray emission. Particle acceleration occurred a few days before radio-jet ejections for two of the four flares, meaning that the process of jet formation implies the production of very energetic particles. In Cygnus X-3, particle energies during the flares can be thousands of times higher than during quiescent states.

2.
Eur Rev Med Pharmacol Sci ; 26(1): 278-283, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35049005

RESUMEN

A case of multiple arterial thrombosis/embolisms in a 74-year-old Caucasian man with no other cardiovascular risk factors who received Ad26.COV2-S vaccine 16 days before is reported. The unusual presentation required a longer diagnostic workup. The clinical manifestations and the therapy-specific response suggest an unusual presentation of Vaccine-induced immune thrombotic thrombocytopenia (VITT).


Asunto(s)
COVID-19 , Embolia , Vacunas , Ad26COVS1 , Anciano , Vacunas contra la COVID-19/efectos adversos , Humanos , Masculino
3.
J Hazard Mater ; 390: 121899, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-31879115

RESUMEN

Waste electrical and electronic equipment (WEEE) can contain brominated flame retardants (BFRs) that pose a threat to human health and the environment. In addition, Br-containing plastics reduce the recycling potential of WEEE. In order to gain a better insight into the distribution of Br in plastics from WEEE, the total concentration of Br was measured on the level of device types and plastic components using handheld X-ray fluorescence (hXRF). In 35 % of the sample size (882 components from 369 different devices, which originate from 6 device types) Br was detected, 5 % exceeded the RoHS limit. Only few and older devices contained high Br concentrations, while the majority were below the RoHS limit and could be recycled. In addition, 18 different plastic types were identified by infrared spectroscopy, with acrylonitrile butadiene styrene being the most abundant (44 % of all samples). Manual dismantling of devices into individual plastic components enabled us to examine Br hotspots and the variety of plastic types in WEEE. Based on this analytical procedure, WEEE recyclers could exclude certain equipment or plastic components (e.g. power supplies or PC housings) directly on-site prior to WEEE recycling and shredding in order to produce high-quality recycled products and avoid cross-contamination.

4.
Ultrasound Med Biol ; 34(8): 1261-71, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18394777

RESUMEN

Management of chronic ulcers in the lower extremities is still a challenge for patients and health providers. Recent studies showed extracorporeal shock waves (ESW) as effective in stimulating growth factors, inducing angiogenesis and healing of fractures and injuries. This study was planned to investigate the opportunity of introducing the ESW in the treatment of chronic wounds. Thirty consecutive patients with chronic posttraumatic, venous and diabetic ulcers, unresponsive to conservative or advanced dressing treatments, were counseled about the use of ESW as alternative treatment for their wounds. Thirty-two wounds were treated and 16 wounds healed completely within six sessions of ESW. In all of the nonhealed wounds, decrease of the amount of exudates, increased percentage of granulation tissue compared with fibrin/necrotic tissue and decrease of wounds' size were statistically significant after four to six sessions of ESW (p < 0.01). Significant decrease of pain was reported (p < 0.001). Comparison with a control group of 10 patients with chronic ulcer treated on the basis of regular dressings confirmed the statistical significant improvement in the healing process (p < 0.01). ESW therapy seems to be a safe, feasible and cost-effective treatment for chronic ulcers in the lower extremities. Further research and clinical trials are necessary to evaluate dose and time intervals of sessions to standardize a protocol of treatment in the management of chronic wounds.


Asunto(s)
Úlcera Cutánea/terapia , Terapia por Ultrasonido/métodos , Cicatrización de Heridas , Anciano , Vendajes , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Úlcera del Pie/patología , Úlcera del Pie/terapia , Humanos , Úlcera de la Pierna/patología , Úlcera de la Pierna/terapia , Masculino , Persona de Mediana Edad , Dolor/patología , Manejo del Dolor , Úlcera por Presión/terapia , Úlcera Cutánea/patología , Estadísticas no Paramétricas , Terapia por Ultrasonido/instrumentación , Úlcera Varicosa/terapia
5.
Science ; 327(5966): 663-5, 2010 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-20044540

RESUMEN

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.

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